Refrigerator doors and actuating mechanism



Aug. 30, 1960 G. MUFFLY 2,950,911

REFRIGERATOF. D OORS AND ACTUATING MECHANISM Original Filed July 10, 1951 IN VEN TOR. Ze/f/r fa/fly REFRIGERATOR DOORS AND ACTUATING MECHANTSM Glenn Muiiiy, 1541 Crestview Drive, Springfield 32, @hin 4 Claims. (Cl. 268-63) This application is a continuation of my copending application, Serial No. 235,920, filed July 10, 1951, now abandoned.

The invention has to do with mechanically operated doors for a household or commercial refrigerator and represents an improvement over the mechanism disclosed in my U.S. Patent No. 2,410,672, issued November 5, 1946.

lt was formerly the practice to make the larger sizes of household refrigerators with two doors for access to the food compartment, but in recent years quite large household refrigerators have been equipped with one large door and at present most of these doors are the full width of the cabinet. This causes the door to swing ou-t into the kitchen a distance equal to the full width of the refrigerator, which is very inconvenient in modern narrow kitchens, particularly in view of the fact that architects often reverse one set of plans for a residence or apartment dwelling to produce another floor plan. This causes the building of many left-handed kitchens in which it is necessary to use a refrigerator having its door hinged at 3 the left instead of a standard production refrigerator hinged at the right. A great deal of inconvenience and additional expense is entailed in obtaining left-hand refrigerators for those few locations which must have them. There are also some kitchens in which the refrigerator is placed vbetween other iixtures, sometimes being approached from the right side and sometimes from the left side.

It is an object of this invention to provide a refrigerator having two doors hinged at opposite sides of the storage space and meeting at the vertical center line thereof without the use of any middle vertical member against which the doors close.

Another object is to provide doors which when opened extend forwardly of the front of the refrigerator a minimum distance.

A further object is to provide for so locating the hinge axes of the doors that either may swing substantially to its full opening without extending beyond the plane of the side wall to which the door is hinged.

Still another object is to provide power-actuated means for opening and closing the doors in response to the closing of an electrical circuit either manually or automatically in response to a signal on the order of the so-called electric eye or other radiant means.

Another object is to provide a refrigerator with twin doors and a system for actuating them in synchronism, either manually or by means of a motor.

An additional object is to provide for gradual acceleration of door movement to eliminate the hazard of injury to small children who may inadvertently actuate the dooroperating device.

A further vobject is to provide frictional or yieldable means for the transmission of energy to a refrigerator door or to actuate it with a low-powered motor capable of being stalled without damage thereto so that no damage A 2,950,911 Y Patented Aug. 30, 1960 will result to a person being caught by the door during its closing motion.

A still further object is to provide door actuating means which is adjustable between at least two positions, in one of which thedoor is opened through the maximum number of degrees of movement and in another the door is opened a lesser number of degrees so as to avoid interference with an adjacent wall or furniture.

In the drawings:

Figure 1 is a top View, broken to show some parts in section, of a refrigerator sho-wing the doors and one form of mechanism to actuate them;

Fig 2 is an enlarged detail drawing of the hinge for the left-hand door;

Fig. 3 is a partial rear View of the motor-driven mechanism in Fig. l;

Fig. 4 is a ViewY `of the base of the cabinet as seen from the right side, partially broken away'to show the foot pedal and its connections; and

Fig. 5 is a partial top View showing a portion of Fig. 1 as modiiied for manual actuation of the doors without use of the motor and gearing.

v Referring to Fig. 1, the refrigerator 10 is equipped with vdoors 12 and 14, hinged respectively at 16 and 18. The Vright-hand door 12is shown by broken lines at position 12 open` to the maximum extent which does not cause it to strike the kitchen wall indicated at 20. The left-hand door 14 is similarly shown by broken lines at 14 as fully opened to substantially the full width of the food storage space of the refrigerator. The hinge pin or shaft 16 or 18 of each door is connected with the part ofthe hinge which is attached to the door through the medium of a torsion spring 24. Each of the shafts 16 and 18 has attached thereto orfformed integrally thereon a crank arm 26 or 28 which is provided with two holes for selective attachment of a crank-operated connecting rod 30. The opposite end of each connecting rod is equipped with a bearing to t a crankpin 32 on one o-f the gears 34 or 36. These gears are driven by the pinion 38 on shaft 40, which is` driven through the over-running clutch 42 by worm wheel 44 and worm 46, which is carried by the shaft of the motor 4S. Assuming that each gear 34 and 36 has 60 teeth, that the pinion 38 has 12 teeth, that worm wheel 44 has 28 teeth, that the worm 46 is single threaded and that the motor operates at 1800 rpm., it will be seen that each gear rotates 1/2 turn for 70 revolutions of the motor shaft which, assuming full motor speed, would be accomplished in something over one second. The actual time of opening or closing of the doors will, however, be somewhat greater because of the lag in acceleration `of the motor to its full speed. Y Y v The motor 48 is energized by closing of the switch 50 which is open in Fig. 1 due to pin 52 being depressed by switch lever 54. Operation of the foot pedal 56 moves the bellcrank 58 and thereby the gear 34 which turns the gear 36 carrying pins 60, allowing the switch 50 to reclose. This starts the motor 48 and thereby continues operationof gears 34 and 36 after the user has released the foot pedal 56. When the doors reach their open position as shown by broken lines in Fig. 1, the other pin 60 reopens the switch and the motor stops with the doors in the open position until the foot pedal is again depressed to start the gears and re-energize the motor. This restarts the gears 36 and 34 in their same directions of rotation. The operator releases the foot pedal as soon as the doors have started to close and their movement continues until aV pin 60 again strikes the lever 54 and reopens the switch.

As mentioned previously, each arm 26 and 28 is provided with two holes, in one or the other of which a pin 62 is placed. In Fig. 1 this pin is placed in the hole located at the shorter radius from the left-hand hinge shaft 18. In the right-hand crank 26 the pin 62 is placed in the hole located at the greater radius from the hinge shaft 116, thereby reducing the angular movement of the door 12. The two holes in each crank are so located as to be equally radially distant from the position of crankpin 32 of the corresponding gear 34 or 36 when the door is in its closed position. The shift from one hole to the other makes no change in the closed position of the door but does modify the open position.

As the two gears 34 and 36 are rotated the connecting rods 30 open and close the doors 12 and 14 by virtue of the fact that the arms 26 and 28 are tixed to the shafts 16 and 18 which serve as hinge pins for the doors. During the opening movement of the doors this connection is positive because of the fact that the stops 642 on each of the shafts 16 and 18 engage the door portions .66 of the hinges as shown in Fig. 2. The hinge pin 18 turns freely in the hinge part 67 which is attached to the body of the cabinet. The coil spring 24 is under torsion, holding the stop 64 against the shoulder 68 of the door portion 66 of the hinge while the opposite end of the spring is anchored to shaft 18 at 69. The doors are opened by positive application of power, starting slowly, accelerating at mid-movement anddecelerating as the doors reach their open positions.

It will be seen that the connecting rods 30 and crankpins 32 are approximately at their dead center positions when the doors are closed and again when the doors are open. At these two dead centers positions the actuating arrn 54 of the switch 50 is depressed by one of the pins 60, thus opening the switch. A slight rotation of the gear 36 will move the pin away from arm 54, thus allowing the switch 56 to reclose, energizing the motor 48, which drives the pinion 38 through the ratchet or over-running clutch 42. The motor 48 will continue to operate until the arm 54 is engaged by the other pin 60, whereupon the motor circuit is opened and the doors are stopped in either their open or closed positions as the case may be. In order to provide for reclosing of the switch 50 to energize the motor l48 for the next operation ofthe doors, whether it be to reclose them or to reopen them, I have provided the ratchet, or pawl 70 which normally stands in the positions indicated by solid lines in Figs. 1 and 3. This pawl is part of bellcrank 58 which is offset and loosely pivoted so that it tilts before rotating when moved by foot pedal 56 through the medium of linkage shown in Fig. 4.

The user of the refrigerator wishing to open or close the doors depresses the foot pedal which actuates the bellcrank 72 and rod 74, the latter being connected with the upper bellcrank 58. Due to the offset shape of bellcrank 58 its first movement is -to tilt against the action of the spring 76, best seen in Fig. 3, moving the pawl 7@ from its original positionto the position 7tl' (Fig. l) whereupon further depression of the foot pedal rotates the bellcrank 58 to bring the pawl to the position itl thus rotating the gear 34 a few degrees and again clearing the gear teeth so that the gear can continue rotation under the power supplied by the motor 4S. Release of the foot pedal allows the bellcrank 58 to rst tilt on its pivot, moving pawl from the position 70" to the posiiton '70"'. Then the bellcrank S8 is rotated, moving its pawl back to the original position 70, by means of the spring 76.

Assuming that this action has been to open the doors, it will be seen that the next operation of the foot pedal will again cause the pawl '70 to turn the gear 34 through a few degrees of its rotation and then pass out of engagement with the gear so that the motor 48 is -free to complete the reclosing of the doors. During the reclosing of the doors, it will be seen that each of the stops 64 (Fig. 2) is moved in the direction which would separate it from the shoulder 68 on the door portion 66 of the hinge, but that these stops and shoulders are held ,4 in contact by the spring 24. The purpose of this spring is to allow either or both doors to be stopped from closing notwithstanding the movement of the gears 34 and 36 which will continue until the next opening of the electrical circuit by the switch 50. This is a safety provision to avoid injury to a person or to the mechanism in the event of accidental blocking of door movement in the closing direction, for example, in the event that the user or a child depresses the pedal while the doors are open and is caught by the reclosing of the doors.

The torsion of the springs 24 is suicient to hold the doors closed against their soft gaskets 78 but not sutilcient to cause injury to a person. Due to the use of soft door gaskets and the fact that both gaskets are cornpressed by a toggle action at the vertical Contact between the doors, it is not necessary to make the springs 24 stii enough to endanger even a small child. The doors can be closed by a spring no stronger than is common on screen doors of residences. As shown, the gasket 78 of right-hand door 12 runs vertically in the front of the gap between doors while the gasket 78 of door 14 is at the rear of the same gap. This provides a double gasket in the plane where doors contact each other.

The shaft of the motor 48 carries the worm 46 which drives the worm gear 44 which in turn drives the pinion 38 through the medium of a ratchet or over-running clutch 42. This ratchet device allows the ratchet or pawl 78 to move the two gears 34 and 36 and the pinion 38 without rotating the worm gear 44. T-he depression of the foot pedal 56 needs only move the gears far enough to close the motor circuit in the switch 50. This amount of movement causes very little movement of the doors due to the positions of the crankpins 32 at or near dead center positions, yet this movement is preferably made sufficient to denitely move the crankpins from idead center positions so that in the event of current failure the user can open or close the doors manually. Even without actuation of the foot pedal the user can open either door manually against the action of its spring 24, thus access to the interior of the refrigerator is possible during failure of the electric current.

lThe hole at extreme end of each arm 26 and 28 is so located that a half revolution of gear 34 or 36, providing the maximum movement of the connecting rod, opens the door to the extent of bringing its exterior curved surface into substantially tangential relationship with the plane of the adjacent side of the cabinet. This allows the refrifrerator to be placed in either a right-hand or a left-hand corner of the kitchen. Normally, there is room for at least one of the doors to swing to a greater opening, which is accomplished by moving the pin 62 from the end hole to one nearer the hinge axis. This wider opening of a door with the pin moved as described is illustrated by the left-hand door 14, of Fig. l. In case there is no wall adjacent either side ofthe refrigerator, both pins 62 can be located in the holes which provide the wider opening of the doors. Since the two doors contact each other on the central line of the cabinet, no vertical stile is required between the doors and the user has free access to the full width shelves when the doors are open.

The top of the outer shell of the refrigerator is a small distance above the top of the upper insulated wall to provide room for the door operating mechanism above described. The front central portion of the space between the top of the outer shell and the top of the liner 80 is utilized to provide a small storage compartment 82 for butter, which should be maintatined at a somewhat higher temperature than prevails in the main storage portion of the refrigerator. This butter compartment 82 is seen in Fig. 1 and has relatively thin insulated walls separating it from the main food compartment and from the top of the outer shell. The butter compartment may if desired be provided with a thermostatically controlled heating element or with thermostatic control of heat'transfer Vfrom it to the main food compartment so as to maintain its temperature within prescribed limits.

Fig. 5 shows the rear middle portion of Fig. 1 as arranged for manual operation, omitting the motor and gears. The pull rod 74, actuated as shown in Fig. 4, is mechanically linked With the connecting rods 30 to actuate the doors without the aid of a motor. Instead of being connected with the bellcrank 58 as in Figs. 1 and 3, the rod 74 is in Fig. 5 connected with crank 84 which is keyed to a shaft carrying a crank 86 on either end. These cranks actuate rods 88, either or both of which may have a slot 89, each rod 88 being arranged to push a lever 90, to which rods 30 are pivoted.

Stepping on pedal 56 the user furnishes the energy which acts through this mechanism to move both doors, each in its opening direction. The weight applied to the foot pedal must be sucient to cause the spring 92 to stretch. At the start of this movement the hinge springs 24 aid in rotating the shafts 16 and 18 until the stops 64 re-engage the shoulders 68. The springs 24 may be omitted, using plain hinges and threading the pins 62 directly into tapped plates on the doors if desired. In that event the spring 92 will replace the springs 24 in taking up the slack back to the pedal 56, holding it against its stop and in supplying the spring pressure against the gaskets 78.

In either case, the user bears down on foot pedal 56 until the spring 92 passes over the xed pivot 94, after which this spring urges each door in its opening instead of its closing direction. The levers move forward to their dotted positions or farther depending upon where a stop is provided. If no special stop is provided, the doors will be opened until one of them is stopped by an obstruction or until some other limit is reached such as the contact of pedal 56 with the floor on which the refrigerator rests.

To reclose the doors the user need push only one of them in its closing direction until the spring 92 is carried past its position of maximum extension, after which this spring will complete the closing of both doors. The spring 92 then holds both doors closed, taking the slack out of linkage between 56 and the doors, and it also holds the pedal 56 up against its stop, which may be on the cabinet or on the door 12.

The pedal 56 is preferably located below the righthand door 12 so as to extend forward of it as seen in Fig. l, but not extending forward of the foremost portion of the doors. This provides easy access to the pedal without allowing it to interfere with moving the cabinet through the kitchen door. For the same reason I prefer not to place any handles on the doors where they may be in the way. In place of door handles each door may be provided with a recess which provides a hand hold for pulling the door open, as at 96 in Fig. 1. These hand holds are in the tops of the doors and readily accessible from outside when the doors are closed. They are primarily for emergency use, such as to open the motor-actuated doors when current is not connected or has failed. The hand holds are not necessary with the arrangement shown in Fig. 5. In Fig. l the doors are started to open by the foot pedal and if the motor is not energized the doors can be opened either by hand or by repeated operation of the foot pedal.

The pedal 56 and the crank arm 98 (Fig. 4) may be made in one piece, but I prefer to mount them on a shaft, placing the arm 98 at the extreme right of the cabinet base where it will not interfere with the condensing unit, with a lower extension of the food storage space, nor with a freezer drawer such as I have shown in my copending U.S. patent application, Serial No. 74,528, filed February 4, 1949, now Patent No. 2,709,343, issued May 31, 1955.

The doors as shown in Fig. l will always open simultaneously when actuated by the motor, though one may be set to open to a greater angle than the other. Either can, however,'be manually opened `while the other remains closed. This is provided for in Fig. 5 by making one or both of the rods 88 with a slot 89 in one end, as shown. This allows either door to be opened by hand independently of the other door, its lever 90 then coming to rest with the spring 92 passing into alignment with the xed pivot 94 so that the spring is not elective to move either door. By providing for more angular movement of the levers 90 the manual opening of either door will carry the spring 92 past center and cause the other door to open. y

The rod is preferably threaded at its forward end to receive the eye 102, thus providing an adjustment to take up lost motion and compensate for wear in the linkage. This provides for the spring 76 or the spring 92 holding the pedal 56 up against its stop, making the full pedal movement available and preventing any rattling of the linkage. Y

The doors 12 and 14 are shown curved, but they might be flat. It is preferred that they meet some distance forward of the plane of their hinge axes in order that the springs 24 or spring 92 will continue to urge the doors into contact with each other when closed.

Fig. 3 provides a rear view of the bellcrank 58 and its spring 76 which has one end anchored at 104 to the mounting plate 106. This plate is bent to extend above the top insulated wall of the cabinet and carry the studs 108 and 110 on which gears 34 and 36 are mounted. It may also extend to support the switch 50 if desired.

An optional method of starting door movement is to provide a switch, as at 112 in Fig. 1, for closing the circuit to motor 48 when the switch 50 is in the open position of Fig. l. The switch 112 may be manually operated by the foot pedal 56 or otherwise, as by the relay device 114 in response to an electric eye or other signal pick-up device.

The refrigerating system is not shown except for the condenser 116. The cooling element or elements may be located in any desiredmanner and the system may be of any suitable type.

Fig. 1 shows a rack 120 attached to the inner side of door 12 and shaped to clear shelves 122 in space 22. Such use of the extra space afforded by the door curvature may include both doors with some variation of form between the devices attached to the two doors. It is preferred that the frozen food compartment be equipped with a separate door or that it be located in a drawer of the type disclosed in my U.S. lpatent application, Serial No. 74,528 above mentioned.

What is claimed is:

1. In a refrigerator cabinet enclosing a storage compartment, means forming an opening through an outer wall of said cabinet for access to said compartment, a door for closing said opening, power transmission means for actuating said door, said transmission means including a yieldable drive in the direction of closing the door and a relatively positive drive in the direction of opening the door, and means for actuating said transmission means to move the door and to stop at the position which normally represents completion of door movement in either direction.

2. In a cabinet having an opening for access to its interior, a door arranged to close said opening, a motor and a power transmission means for actuating said door, said transmission means including a yieldable element through which power is transmitted from said motor to said door while closing the door and positive drive abutments for transmission of power from said motor to the door to open the door, said yieldable element allowing manual opening of the door when the motor has stopped with the door in its closed position.

3. In a refrigerator cabinet enclosing a storage compartment, means forming an opening through an outer wall of said cabinet for access to said compartment, a door for closing said opening, a motor and power transmission means for actuating said door, Vsaid transmission means including a yieldable drive in the directionrof closing the door and a more positive drive in the direction of opening the door, a switch for energizing said motor and then deenergizing it at completion of door movement in either direction, and means responsive to a slight movement of the door in its closing direction to actuate said Switch for the purpose of completing the closing of the door, said yieldable drive allowing stoppage of closing movement of the door in the event of meeting an ohstruction and allowing manual openingr of the door from its fully closed position without aid of the motor.

4. In a refrigerator cabinet having an access opening, a pair of doors hinged at opposite sides `of said opening and contacting each other when closed, an easily compressible gasket xedly mounted on the edge of one of said doors which faces away from the hinge axis of said one door, said gasket forming the part of said door which makes contact with its mating door when both doors are closed, a motor of unidirectional rotary type, a power transmission mechanism connecting said motor with said doors to alternately open and synchronously close them, an electric switch connected in the power supply circuit of said motor, actuating means connected with said switch to open it when said mechanism has moved to its position which corresponds with the open position of said doors and also when its position corresponds with the normally closed position of said doors, manually operable means for initiating movement of said doors in either their opening or closing directions and for energizing said motor, and yieldable means forming a part of said transmission mechanism through which power is transmitted during its movement toward its closed-door position, said yieldable means allowing either door to be opened manually and providing for stoppage of either or both doors in the event of an obstruction in the path of door-closing movement.

References Cited in the le of this patent UNITED STATES PATENTS 137,951 Palmer Apr. 15, 1873 1,508,580 Schoelkopf Sept. 16, 1924 1,768,173 Tucker June 24, 1930 1,824,109 'Allard et al. Sept. 22, 1931 1,918,911 Hull July 18, 1933 1,944,618 Sweeley et al Jan. 23, 1934 2,227,556 Roberts I an. 7, 1941 2,298,158 Piron Oct. 6, 1942 2,408,132 Weeks Sept. 24, 1946 2,663,916 Millman Dec. 29, 1953 

